As the search for oil and gas has increased, so also have the various types of drilling rigs increased. One particularly advantageous type of drilling rig is that which is capable of drilling at any angle from the horizontal to the vertical. Such slant-type drilling rigs are advantageous in that the bore hole may be drilled at almost any angle.
While slant-type drilling rigs are advantageous in permitting drilling at any angle, they are disadvantageous in that the means for lifting the drill pipe into the drilling position are very cumbersome. Conventional vertical drilling rigs employ a draw-works system to lift the drill pipe and place it in vertical alignment with the bore hole. Such a draw-works type system is not possible with a slant-type drilling system as the drill pipe must be angularly aligned with the bore hole and, hence, a draw-works system is not readily usable as the draw-works is displaceable co-axially with the bore hole.
An additional disadvantage of a slant-type drill rig is that means must be provided for supporting the drill pipe along its length which means do not interfere with the operation of the rotary spindle or table which is used to turn the drill pipe and the drill bit. Conventional vertical drill rigs do not require support means for the drill pipe as the length of drill pipe is supported in the bore hole and is aligned vertically with the spindle and, hence, has no horizontal component.
Consequently, a new and unique system for lifting 1 drill pipe from a horizontal storage position to an angular position associated with a slant-type drilling rig is advantageous. Such a system must be capable of placing the drill pipe in mounts for supporting the drill pipe along its length during the drilling operation. Such support mounts must not interfere with the operation of the rotary spindle during its traverse along the length of the drill rig.